The present invention relates to a method of pretreating suspended containers of a flexible material and an arrangement for performing this method.
It is known to use containers of flexible material, as storage silos by suspending them in upright positions. Such containers may accommodate large amounts of material therein, for example, more than 20 tons. It has, however, been found that the flexible container essentially elongates upon receiving the material therein and subsequently goes back after discharging the material therefrom to its original length with only small residual deformation. Such movements of the flexible container in the opposite directions are especially undesirable in the cases where the discharging means of the container is connected to rigid systems, such as metering or dosing devices or conveyers. If the flexible container is connected to the rigid system, in an initial position of the container before an elongation thereof, a subsequent elongation of the container upon receiving the material therein, causes an overhanging of the container, leading to bending of some of its wall portions. This creates difficulties because it interferes with proper discharge of the material from the container. In cases where the container is connected to the rigid systems only after it has received the material to be stored, it is necessary to take into account the stresses resulting from a subsequent shortening of the container after a discharge of material therefrom, which can damage the rigid systems connected to the container.